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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Serie: IEEE Press Series on Information and Communication Networks Security
- Sprache: Englisch
- Veröffentlichungsjahr: 2015
This book is a comprehensive study on OPS networks, its architectures, and developed techniques for improving its quality of switching and managing quality of service. The book includes: * Introduction to OPS networks, OOFDM networks, GMPLS-enabled optical networks, QoS in OPS networks * Hybrid contention avoidance/resolution schemes in both long-haul and metro optical networks * Hybrid optical switching schemes
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QUALITY OF SERVICE IN OPTICAL PACKET SWITCHED NETWORKS
Akbar Ghaffarpour Rahbar
Sahand University of Technology
Copyright © 2015 by The Institute of Electrical and Electronics Engineers, Inc.
Published by John Wiley & Sons, Inc., Hoboken, New Jersey. All rights reserved. Published simultaneously in Canada.
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Library of Congress Cataloging-in-Publication is available.
ISBN 978-1-118-89118-6
To my parents and my family
CONTENTS
PREFACE
REFERENCES
ACKNOWLEDGMENTS
ACRONYMS
GLOSSARY
SYMBOLS
CHAPTER 1 INTRODUCTION TO OPTICAL PACKET SWITCHED (OPS) NETWORKS
1.1 Optical Fiber Technology
1.2 Why Optical Networks?
1.3 Optical Networking Mechanisms
1.4 Overview of OPS Networking
1.5 Optical OFDM-Based Elastic Optical Networking (EON)
1.6 Summary
References
CHAPTER 2 CONTENTION AVOIDANCE IN OPS NETWORKS
2.1 Software-Based Contention Avoidance Schemes
2.2 Hardware-Based Schemes
2.3 Formulation of Even Traffic Transmission in Slotted OPS
2.4 Summary
References
CHAPTER 3 CONTENTION RESOLUTION IN OPS NETWORKS
3.1 Hardware-Based Contention Resolution Schemes
3.2 Software-Based Contention Resolution Schemes
3.3 Summary
References
CHAPTER 4 HYBRID CONTENTION AVOIDANCE/RESOLUTION IN OPS NETWORKS
4.1 Hybrid Contention Resolution Schemes
4.2 Hybrid Contention Resolution and Avoidance Schemes
4.3 Summary
References
CHAPTER 5 HYBRID OPS NETWORKS
5.1 Hybrid Asynchronous and Synchronous OPS Networks
5.2 Hybrid OPS and OCS Networks
5.3 Comparison of Hybrid OPS Schemes
5.4 Summary
References
CHAPTER 6 METRO OPS NETWORKS
6.1 OPS in Star Topology
6.2 OPS in Ring Topology
6.3 Summary
References
Index
IEEE Press Series on Information and Communication Networks Security (ICNS)
EULA
List of Tables
Chapter 2
Table 2.1
Table 2.2
Table 2.3
Table 2.4
Table 2.5
Chapter 3
Table 3.1
Table 3.2
Table 3.3
Table 3.4
Chapter 4
Table 4.1
Table 4.2
Table 4.3
Table 4.4
Table 4.5
Table 4.6
Chapter 6
Table 6.1
Table 6.2
Table 6.3
Table 6.4
Table 6.5
Guide
Cover
Table of Contents
Preface
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PREFACE
Welcome to the era of unlimited communications, video-centric applications, and Internet! Internet applications require both bandwidth and Quality of Service (QoS) because of a huge number of Internet users and growing number of real-time applications (such as 3D TV, ultrahigh-definition TV, video-on demand, Internet Protocol TeleVision (IPTV), video-conferencing, Internet gaming, voice over IP, etc.) that need different levels of QoS. IP networks consist of core networks and access networks. By increasing IP traffic, access networks can grow in both size and count [1]. For example, traffic of broadband access networks such as ADSL and Fiber To The Home (FTTH) is continually increasing every year. To transport the huge traffic offered by IP networks, the core networks capabilities must be increased to avoid them from becoming bottleneck for IP traffic. This could be a problem when the network bandwidth is limited, the network supports only the best effort traffic, and the Internet traffic does not have a uniform characteristic.
The need for more and more bandwidth forces us to think of more granularity. The best promising solution is to use Wavelength Division Multiplexing (WDM) all-optical networks in core networks. Note that an optical network that uses optical transmission and keeps optical data paths through the nodes from source to destination is called all-optical network. Due to the fact that all-optical networks use photonic technology for the implementation of both switching and transmission functions, signals in these networks can be maintained in optical form without any conversion to the electronic domain resulting in much high transmission rates. All-optical networking with deployment of Dense Wavelength Division Multiplexing (DWDM) appears to be the sole approach to transport the huge network traffic in future backbone networks. The DWDM technology provides the multiplexing of many wavelength channels in a single optical fiber, resulting in several Tbits/s bandwidth capacity.
Similar to the electronic domain in which packet switching is the most granular method of switching, the most promising technique for optical core networks could be Optical Packet Switching (OPS) due to its high throughput and very good granularity and scalability. In an OPS edge node, a header is attached to each client packet received from a legacy network, where the header includes the information about source edge node, destination edge node, and content of packet payload such as its length. The packet is then transmitted in the optical domain, called an optical packet, toward the OPS network. In OPS, an optical packet stays in the optical domain inside the core network and switched optically. The optical packet can only be converted to the electronic domain in its destination edge node. Packet switching provides connectionless transmission of packets. Thus, there is no need to establish a path (i.e., a circuit) between source-destination nodes like in circuit switching. However, contention of optical packets in the core network is the major problem in OPS networks.
Since different applications need different levels of QoS, service differentiation must be considered in optical networks as well. Under the best-effort service in which no guarantees are given to any packet regarding loss rate, delay, and delay jitter, all traffic in the network is equally treated. This will, in turn, degrade the QoS requirements for real-time traffic. Thus, having a QoS-capable optical backbone network will be a requirement in which low latency, low jitter, low loss, and bandwidth guarantees must be provided for real-time traffic.
For providing QoS in OBS networks, [2] details (a) the basic mechanisms developed for improving end-to-end QoS and (b) relative and absolute QoS differentiation among multiple service classes. On the other hand, for OCS networks, the work in [3] focuses on the methods developed for service-differentiated and constraint-based wavelength routing and allocation in multi-service WDM networks. However, there is no comprehensive work on QoS in OPS networks.
In future, OPS networks must be setup for worldwide communications in order to transport the huge traffic generated by Internet users and applications. In addition, research and development on optical communication networking have been matured significantly during the last decade to the extent that some of these principles have moved from the optical research laboratories to formal graduate courses. Moreover, there are a large number of experts working on designing optical devices and physical-layer of optics that are interested in learning more about OPS network architectures, protocols, and the corresponding engineering problems in order to design new state-of-the-art OPS networking products. Finally, there are many books written for device level of optical communications, and there are even devices suitable for OPS. However, there is almost no work dedicated solely for system level of OPS (say architectures and protocols), improving quality of service, and the operation of OPS networks.
In general, there are some books published for covering optical networking such as [4-10]. However, the number of published books dedicated to the system level of OPS is limited to OPS in access networks [11], design of optical buffers for OPS [12], edge node design for contention avoidance in slotted OPS [13], scheduling in star-based OPS networks [14], and OPS for ring networks [15].
This book provides a comprehensive study on OPS networks, its architectures, and developed techniques for improving its quality of switching and managing quality of service. This book is organized in six chapters, each covering a unique topic in detail:
Chapter 1 provides an introduction to OPS networks, its architectures, and QoS in OPS. Since many optical networking books have stated optical systems in much detail, this chapter does not include them. In addition to OPS networks, GMPLS-supported optical networks and optical networks based on Orthogonal Frequency Division Multiplexing (OOFDM) are studied in this chapter.
Chapter 2 describes contention avoidance schemes proposed for OPS networks in which edge switches send optical packets to the OPS network in a way to reduce their collisions. Broadly, these schemes are classified as either hardware-based or software-based.
Chapter 3 details contention resolution schemes proposed for OPS networks in which OPS switches resolve the collision of contenting optical packets. In general, contention resolution schemes are classified as either hardware-based or software-based.
Chapter 4 studies the hybrid contention resolution schemes that use a number of contention resolution schemes in the same architecture in order to reduce optical packet loss rate. In addition, hybrid contention resolution and contention avoidance schemes are reviewed that can efficiently reduce optical packet loss rate in a cost-effective manner.
Chapter 5 describes hybrid optical switching schemes in which OPS networking is combined with another optical switching technique (say optical circuit switching) in order to improve the performance of traffic transmission in the optical domain.
Chapter 6 states different OPS architectures designed for metro area. These networks are mainly based on ring and star topologies with active optical switches.
This book is a useful resource for students, engineers, and researchers to learn more about optical packet switched networking from system level points of view. It is intended as a textbook for graduate level and senior undergraduate level courses in electrical engineering and computer science on (advanced) optical networking. Knowledge about computer networks is a prerequisite for understanding this book. For advanced optical networks course relevant to OPS, the book can be entirely used.
Reasonable care has been taken in eliminating any types of errors. However, readers are encouraged to send their comments and suggestions to the author via e-mail. I personally hope that this book will give the reader enough information in OPS networks and motivate his/her interests to develop efficient, QoS-capable, and cost-effective OPS networks suitable for future core optical networks.
AKBAR GHAFFARPOUR RAHBAR
Sahand University of Technology [email protected]
REFERENCES
A. Shami, M. Maier, and C. Assi.
Broadband Access Networks: Technologies and Deployments
. Springer, 2009.
K. C. Chua, M. Gurusamy, Y. Liu, and M. H. Phung.
Quality of Service in Optical Burst Switched Networks
. Springer, 2007.
A. Jukan.
QoS-based Wavelength Routing in Multi-Service WDM Networks
. Springer, 2001.
B. Mukherjee.
Optical WDM Networks
. Springer, 2006.
R. Ramaswami, K. Sivarajan, and G. Sasaki.
Optical Networks: A Practical Perspective
. third edition, Morgan Kaufmann, 2009.
T. E. Stern, G. Ellinas, and K. Bala.
Multiwavelength Optical Networks: Architectures, Design, and Control
. second edition, Cambridge University Press, 2008.
J.M. Simmons.
Optical Network Design and Planning
. Springer, 2008.
V. Alwayn.
Optical Network Design and Implementation
. Cisco Press, 2004.
R. J. B. Bates.
Optical Switching and Networking Handbook
. McGraw-Hill, 2001.
M. Maier.
Optical Switching Networks
. Cambridge University Press, 2008.
K. Bengi.
Optical Packet Access Protocols for WDM Networks
. Springer, 2002.
E. H. Salas.
Design of Optical Buffer Architectures for Packet-Switched Networks: An Optical Packet Buffer Overview
. LAP Lambert Academic Publishing, 2010.
A. G. Rahbar and O. Yang.
OPS Networks: Bandwidth Management & QoS
. VDM Verlag, Germany, 2009.
N. Saberi.
Photonic Networks: Bandwidth Allocation and Scheduling
. LAP LAMBERT Academic Publishing, 2011.
B. Uscumlic.
Optical Packet Ring Engineering: Design and Performance Evaluation
. LAP LAMBERT Academic Publishing, 2011.
ACKNOWLEDGMENTS
To all those wonderful people I owe a deep sense of gratitude especially now that this book has been completed. To my wife and daughter for their consistent patience and encouragement. To the publisher’s staff for their collaboration and project management.
Akbar Ghaffarpour Rahbar
ACRONYMS
3LIHON
3 Level Integrated Hybrid Optical Network
ACK
ACKnowledge
AF
Assured Forwarding
APTB
Aggregated Packet Transmission Buffer
AW
Additional Wavelengths
AWG
Array Waveguide Grating
BE
Best Effort
BER
Bit Error Rate
BH
Burst Header
BP
Buffer Pool
bps
bits per second
BPSK
Binary Phase-Shift Keying
BV
Bandwidth Variable
BvN
Birkhoff and von Neumann
CBR
Constant Bit Rate
COPS
Composite Optical Packet Scheduling
CoS
Class of Service
CPA
Composite Optical Packet Aggregation
CPDU
Control packet PDU
CRSA
Contention Resolution Scheduling Algorithm
CSMA/CA
Carrier Sense Multiple Access with Collision Avoidance
CWDM
Coarse WDM
DA
Distribution-based bandwidth Access
DCF
Dispersion Compensated Fiber
DiffServ
Differentiated Services
DMUX
DeMultiplexer
DR
Deflection Routing
DRwBD
Deflection Routing with Backward Deflection
DRwoBD
Deflection Routing without Backward Deflection
DSF
Dispersion Shifted Fiber
DWDM
Dense WDM
EAP
Even Assignment Problem
EBvN
Efficient BvN
EBvN_FEC
EBvN with Filing Empty Cells
EDFA
Erbium-Doped Fiber Amplifier
EDF
de
Even Density distribution through gauging Frame
EDF
di
Even Distance distribution through gauging Frame
EF
Expedited Forwarding
EON
Elastic Optical Network
ES
Edge Switch
FCFS
First-Come-First-Served
FD
Fair Dissemination distribution
FDL
Fiber Delay Line
FDM
Frequency Division Multiplexing
FEC
Forward Error Correction
FEC
Forwarding Equivalent Class (in MPLS networks)
FF
First-Fit
FIFO
First-In-First-Out
FRWC
Full Range Wavelength Converter
FSC
Fiber-Switch-Capable
FTTH
Fiber-To-The Home
FTWC
Fixed-input/Tunable-output WC
FWC
Fixed Wavelength Converter
GF
Gauging Frame
GMPLS
Generalized Multi-Protocol Label Switching
GST
Guaranteed Service Transport
HCT
High Class Transport
HOPSMAN
High-performance Optical Packet-Switched MAN
HOS
Hybrid Optical Switching
HOTARU
Hybrid Optical neTwork ARchitectUre
HP
High-Priority
HSWC
Hybrid Shared Wavelength Conversion
HTDM
Hybrid TDM
IAS
Impairment-Aware Scheduling
ID
IDentification
ILP
Integer Linear Programming
IP
Internet Protocol
IPD
Intentional Packet Dropping
IPT
Immediate Packet Transmission
IPTV
Internet Protocol TV
ISA1
Ingress Switch Architecture 1 for class-based OPS networks
ISA2
Ingress Switch Architecture 2 for class-based OPS networks
LB
Load Balanced distribution index
LCR
Local Cyclic Reservation
LCR-SD
Local Cyclic Reservation with Source-Destination
LDP
Label Distribution Protocol
LER
Label Edge Router
LGRR
Loan-Grant-based Round Robin
LP
Low-Priority
LRWC
Limited-Range Wavelength Converter
LSC
Lambda-Switch-Capable
LSP
Label Switching Path
LSR
Label Switching Router
MAC
Media Access Control
MAN
Metropolitan Area Network
MBS
Merit-Based Scheduling
MEMS
Micro-Electro-Mechanical Systems
MF
Multi Fiber
MFAW
Multi Fiber + Additional Wavelengths
MI
Minimum Interference, Multilayer Interference
MING
Minimum Gap Queue
MINL
Minimum Length Queue
MP
Mid-Priority
MPBvN
Multi-Processor BvN
MPLS
Multi-Protocol Label Switching
M_PR
Modified Prioritized Retransmission
MPR
Multi-Path Routing
MQWS
Minimum Queue length Wavelength Selection
MUX
Multiplexer
MW-OPS
Multi-Wavelength Optical Packet Switching
NACK
Negative Acknowledge
NBR
Non-Blocking Receiver
NCPA
Non-Composite Optical Packet Aggregation
NCT
Normal Class Transport
NoD
No Deflection
NR
No Retransmission
NRP
Number-Rich Policy
NRPWC
Non-Recursive Parametric Wavelength Conversion
NWB-OPS
Non-Wavelength-Blocking OPS
NZDSF
Non-Zero Dispersion-Shifted Fiber
OBM
Optical Bandwidth Manager
OBS
Optical Burst Switching
OCGRR
Output-Controlled Grant-based Round Robin
OCS
Optical Circuit Switching
O/E/O
Optical/Electrical/Optical
OOFDM
Optical Orthogonal Frequency Division Multiplexing
OP
Optical Packet
OpMiGua
Optical Migration capable network with service Guarantees
OPS
Optical Packet Switching
ORION
Overspill Routing in Optical Networks
OSNR
Optical Signal-to-Noise Ratio
OTDM
Optical Time Division Multiplexing
OVP
OVerspill Packet
OXC
all-Optical Cross-Connect switch
PA
Packet Aggregation
PAU
Packet Aggregation Unit
PDP
Preemptive Drop Policy
PDU
Protocol Data Unit
PLR
optical Packet Loss Rate
PMD
Polarization Mode Dispersion
POADM
Packet Optical Add and Drop Multiplexers
PQOC
Probabilistic Quota plus Credit
PR
Prioritized Retransmission
PS
Packet Scheduler
PSC
Packet-Switch-Capable
PSK
Phase Shift Keying
PTES
Packet Transmission based on Scheduling of Empty Time Slots
PWC
Parametric Wavelength Converter
QAM
Quadrature Amplitude Modulation
QoS
Quality of Service
QoT
Quality of Transmission
QPSK
Quadrature Phase-Shift Keying
RIB
Reservation Induced Blocking
RNENF
Random choice among Neither Empty Nor Full queues
ROADM
Reconfigurable Optical Add/Drop Multiplexer
ROB
Removing of Overdue Blocks
RPWC
Recursive Parametric Wavelength Conversion
RR
Random Retransmission
RS
Reed-Solomon
RSA
Routing and Spectrum Assignment/Allocation
RSVP
Resource Reservation Protocol
SA
Spectrum Assignment/Allocation
SBvN
Separated BvN
SDU
Service Data Unit
SFD
Smoothed Flow Decomposition
SHP
Shortest Hop-Path
SLA
Service Level Agreement
SM/BE
Statistically Multiplexed Best Effort
SMF
Single-Mode Fiber
SM/RT
Statistically Multiplexed Real Time
SOA
Semiconductor Optical Amplifier
SPC WC
Single-Per-Channel Wavelength Converter
SPIL WC
Shared-Per-Input-Link Wavelength Converter
SPIW WC
Shared-Per-Input-Wavelength Wavelength Converter
SPL WC
Shared-Per-Link Wavelength Converter
SPN WC
Shared-Per-Node Wavelength Converter
SPOL WC
Shared-Per-Output-Link Wavelength Converter
SPOW WC
Shared-Per-Output-Wavelength Wavelength Converter
SPR
Shortest-Path Routing
SSMF
Standard Single-Mode Fiber
SWING
Simple Wdm rING
TCP
Transmission Control Protocol
TDM
Time Division Multiplexing
TFWC
Tunable-input/Fixed-output WC
TLWC
Two-Layer Wavelength Conversion
Tout
Timeout
TTL
Time-To-Live
TTWC
Tunable-input/Tunable-output WC
TWC
Tunable Wavelength Converter
VRP
Variety-Rich Policy
WAN
Wide Area Network
WAR
Wavelength Access Restriction
WB-OPS
Wavelength-Blocking OPS
WC
Wavelength Converter
WDM
Wavelength Division Multiplexing
WDS
Wavelength Delay Section
WRN
Wavelength Routed Network
wsc
Waveband-Switch-Capable
wss
Wavelength Selective Switch
wxc
Wavelength Cross-Connect
GLOSSARY
* Notation used in switch sizes, say a switch with a inputs and b outputs is denoted by a*b
x
mod
y
Remainder of x divided by y
Asynchronous OPS
Pure (non-slotted) OPS
Client packet
The upper layer packet arriving at an ingress switch from legacy networks
Conversion ratio
Ratio of total number of WCsused in an N*N OPS switch with W wavelengths to total number of wavelengths in the switch (i.e., N x W)
Core switch
An optical switch that performs switching in the optical domain
Drop link
f fibers connecting a core switch to an egress switch for delivering f optical packets on each wavelength from the core to the edge switch at the same time
Drop port
One fiber connecting a core switch to an egress switch for delivering one optical packet on each wavelength from the core to the edge switch
Egress switch
An edge switch with the function of receiving traffic from an optical network
FDL bank
A bank of FDL buffers that provides delay in range 0 to B x D, where D is a constant delay time and B is the buffer depth
Gbits/s
Gigabits per second
Ingress switch
An edge switch with the function of transmitting traffic to an optical network
Input port
An input fiber to a core switch from a neighbor edge/core switch in a single-fiber network
Input link
f fibers input to a core switch from a neighbor edge/core switch in a multi-fiber network
Legacy network
Any network (including an old network, an Ethernet network, a TCP/IP network, and a SONET/SDH network) connected to an edge switch
Local optical packet
The optical packet either added to an OPS switch by its local ingress switch, or dropped by the OPS switch to its local egress switch
max(
x, y
)
The larger value of x and y
Mbits
Megabits
min(
x
,
y
)
The smaller value of x and y
nf-slot-set
The set of n X / optical packets sent from n ingress switches on the same wavelength channel and on / fibers within a given time slot
nm
Nano meters
ns
Nano seconds
Optical packet
The packet transmitted by an ingress switch to an OPS network that may include one or more client packets
OP set
A set of optical packets transmitted at the same time slot over the available fibers/wavelengths in an ingress switch
OPS core switch
An optical switch that performs OPS switching functionality in the optical domain
Output port
An output fiber from a core switch to a neighbor edge/core switch in a single-fiber network
Output link
f fibers output from a core switch to a neighbor edge/core switch in a multi-fiber network
Slot set
Set of f × W rows in a column of a frame in frame-based scheduling
Synchronous OPS
Slotted OPS
Tbits/s Torrent
Terabits per second
Torrent
All the (class-based) traffic going to the same egress switch in an ingress switch. Therefore, Torrent-i traffic goes to egress switch i
Transit optical packet
The optical packet that passes through an OPS switch toward another OPS switch
Uniform selection
Uniform selection from a list with m items; i.e., selecting an item randomly with probability .
WC bank
A bank of wavelength converters with the same type
